<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width">
<style>
#A {
  /* Dummy layer which is not allowed to squash */
  top: 0;
  left: 0;
  width: 20px;
  height: 20px;
}

#B {
  top: 0px;
  width: 200px;
  height: 20px;
}

#C {
  top: 0px;
  left: 0px;
  width: 40px;
  height: 200px;
}

div {
  position: absolute;
  background: #a0a0ee;
  border: 3px solid #1010ff;
}

iframe {
  backface-visibility: hidden; /* force compositing */
}
</style>
</head>
<body>
  <iframe id="I" width="200" height="240" src="/cross-site/baz.com/title1.html" frameborder="0" allowfullscreen=""></iframe>
  <div id="A"></div>
  <div id="B"></div>
  <div id="C"></div>
</body>
</html>
